The environmentalists who oppose the Keystone XL pipeline are overlooking a fact the size of Canada. The tar sands oil in the Alberta Province is going to be extracted and sold one way or another. There is no way the Canadian government is going to sit on a resource worth billions.

In fact, if the tar sands oil isn't piped to refineries in Port Arthur and Houston, it will most likely be sold to China. That will mean transporting it by pipeline or rail to Canada's western coast, where it will then be loaded onto tankers and shipped to China.

That method will have a greater impact on the environment, from the energy used to power the ships to the threat of tanker spills to the lax refinery standards in China. And contrary to some claims, the tar sands oil is no more difficult to process than some crude that U.S. refineries are already handling.

Oil has environmental drawbacks. We get that. But the reality of the modern global economy is that it runs on oil and will for years to come. That won't change even if new supplies like the tar sands in Canada are choked off for some reason. Oil will simply be more expensive.

This country should support feasible energy alternatives and require more efficient use of petroleum products. In fact, we've been doing that more and more since the oil embargo of the 1970s.

But in the meantime, our farms and factories must have the energy they need. That's why President Obama should greenlight the Keystone XL pipeline. It's the right decision for our environment, and our economy.